Meat spoilage by bacteria: Influencing factors, volatile compounds, and organoleptic alterations

This review provides an understanding of spoilage factors of meat, the spoilage bacteria, the spoilage mode of major spoilage bacteria, and alterations due to spoilage. pH and water activity of meat, packaging atmosphere, and storage temperature affect the growth and activity of spoilage bacteria. The spoilage bacteria cause the production of various compounds. Volatile compounds such as volatile basic nitrogen [ammonia (NH₃) and amines (RNH₂)], alcohols (ROH), aldehydes (RCHO), ketones (RCOR'), and sulfur (S) compounds are generated by decomposition from glycogen, proteins and lipids in meat with various enzymatic (decarboxylase, phosphoketolase, alcohol dehydrogenase, lipoxygenase, acetate kinase, etc.) reactions of Brochothrix thermosphacta, Carnobacterium, Enterobacteriaceae, lactic acid bacteria, Pseudomonas, etc. During the spoilage process, some metabolic activities of bacteria lead to organoleptic alterations in meat. Some bacteria form slime, produce odor-causing substances, or cause color changes during meat spoilage. The information reviewed in this paper may help readers better understand meat spoilage by bacteria; other causes responsible for spoilage are not covered in this paper.